Two copper complexes with imidazole ligands: Syntheses, crystal structures and fluorescence

Abstract

Two copper (imidazole) complexes, namely, [Cu(im)6]Cl2 · 4H2O (1), and [Cu(im)6]Cl2 · 2H2O (2) (im-imidazole) have been synthesized by hydrothermal method. Single-crystal X-ray analysis revealed that the complex 1 belongs to triclinic system, space group P $$ \bar 1 $$ with a = 8.8097(18) Å, b = 9.0812(18) Å, c = 10.586(2) Å; α = 75.08(3)°, β = 83.14(2)°, γ = 61.84(3)°; R 1 = 0.0562, wR 2 = 0.1607. In compound 1, [Cu(im)6]2+ cation and counter anions Cl− alternatively array in an ABAB fashion via N-H...Cl hydrogen bonding. Compound 2 falls into monoclinic system, space group P21/n with a = 8.073(2) Å, b = 13.239(2) Å, c = 15.0810(10) Å; β = 97.940(10)°; R 1 = 0.0434, wR 2 = 0.1243. The equatorial ligands are involved into a complex hydrogen bond network that involves the chloride anions and uncoordinated water molecules. We report there synthesis, crystal structure, thermal stability, IR spectrum and fluorescent property.